Lennox SLP98UHV Installation Instructions Manual page 25

SLP98UHV with Evaporator Coil Using a Separate Drain
Evaporator
Coil
(Trap at coil is optional)
Drain Pan
Piping from furnace and evaporator coil must slope down a minimum 1/4" per ft. toward trap
IMPORTANT
When combining the furnace and evaporator
coil drains together, the A/C condensate drain
outlet must be vented to relieve pressure in or­
der for the furnace pressure switch to operate
properly.
SLP98UHV with Evaporator Coil Using a Common Drain
Evaporator
Coil
(Trap at coil is optional)
Drain Pan
(Unit shown in horizontal left-hand discharge position)
Condensate
Drain Connection
FIGURE 36
(Unit shown in horizontal left−hand discharge position)
Condensat e Drai n
Connection
Piping from furnace and evaporator coil must slope
down a minimum 1/4" per ft. toward trap
FIGURE 38
Page 25
4"min
5"max
5' max.
PVC Pipe Only
SLP98UHV with Evaporator
Coil Using a Common Drain
(Trap at coil is optional)
(1" min. to 2" Max.above
condensatedrain connection)
Condensate
Drain Connection
4"min
5"max
5' max.
PVC Pipe Only
Field Provided Vent
(4" min. to 5" max. above
condensate connection)
.
Evaporator drain
line required
FIGURE 37
(4" min. to 5" Max.above
condensatedrain connection)